An image reading device, such as an image scanner, has a correction process (calibration) function for correcting a correlation between output from a reading unit and a color indicated by this output based on a color sample so as to properly recognize a color of an image formed on a medium and read by the reading unit (for example, refer to Patent Literature 1). Generally, a component functioning as a color sample is provided at a position facing the reading unit as equipment fixed to the image reading device. In the correction process, the image reading device reads the color sample by using the reading unit, and associates a value indicated by a signal output as a reading result with a color of the color sample to determine a color standard.